Conventional glass fibers are useful in a variety of applications including reinforcements, textiles, and acoustical and thermal insulation materials.
Continuous glass fibers are typically produced via bushings for reinforcement and textile applications. Such fibers are typically made of many glass filaments held together by sizing. The glass fibers are often further processed by combining them into continuous strands, yarns and rovings, or by chopping the glass fibers into preselected lengths defined by the end user. Where chopped, the resulting short, straight fiber segments may be mixed with other materials, wet processed into mats such as are used for shingles, or otherwise treated for use. While bushings have significant operational lifetimes, their throughput is limited relative to rotary fiberizing techniques for producing glass fibers.
Short, straight fibers typical of acoustic and thermal insulation materials are made by rotary fiberizing techniques and are interconnected by binders. In such techniques, molten glass is delivered from a furnace to an orificed centrifuge, commonly referred to as a spinner. Fibers produced by the spinner are drawn downward by a blower. A binder, which is required to bond the fibers into a wool product, is sprayed onto the fibers as they are drawn downward. The fibers are then collected and formed into a wool pack. The resulting materials suffer from non-uniform material distribution, the expense of binder, and costs to treat effluent and exhaust air to protect the environment from the impact of organic compounds in the binder.
In addition to insulation materials, other wool products are produced from the wool pack by further compressing and heat setting the wool into boards or panels. Alternately, the wool may be blended with other natural and synthetic fibers to form non-woven materials, and thereafter carded or combed to open up the fiber pack for further processing, such as needling. Carding and combing tends to align the fibers. The blended fibers serve both to open the glass fiber matrix and make the glass fibers amenable to needling by `lubricating` the needling action.
Conventional glass fibers, whether continuous, chopped, or in wool packs have found their way into a wide variety of products. It is desirable to further improve the characteristics of products including glass fibers, and to find new uses for glass fibers which take advantage of glass fiber properties.